Hemsworth strips down to his underwear for a performance in the new comedy "Vacation". And although the scene garnered lots of laughs from movie-goers, the film's star, Applegate, says Hemsworth's physique is no laughing matter.

"It didn't make me laugh because we were just in awe of his abs," Applegate told people.com of filming the scene.

"It got quiet on the set there for awhile."

Applegate, 43, says she remains mystified as to how Hemsworth was able to get into such great shape.

"He said, 'I don't really do anything, I just surf,' and I'm like 'that is not from surfing guy. You don't want to give us your secrets? That is not okay'."